Measurement of high energy neutrons by fission reactions

In most high energy radiation fields, such as those encountered around acce lerators or cosmic rays in the atmosphere, neutrons produce the largest per centage of the hadron dose. In these radiation fields, the neutron spectrum is typically formed by low energy neutrons (evaporation spectrum) and high energy neutrons (knock-on spectrum). Neutron spectrometry and dosimetry are better understood for low energy neu trons (i.e. neutrons with energy below 20 MeV) than for those of higher ene rgies. This paper reports the study of different detectors based on the reg istration of fission fragments of different heavy elements (namely bismuth, gold and tantalum), which have their principal response to high energy neu trons. (C) 2001 Elsevier Science Ltd. All rights reserved.